The reasons I connect her with Hikari :
- she's an automaton
- her hair shape (just look at Hikari's and compare)
- A paraphrase of Tio's background from a Grandia 2 fan site
- Survivor of an ancient war between good and evil, this automaton goes by the name Tio. Although she possesses calculation abilities, it seems she can only act when she is given orders.
She can perform a number of things like cooking, but she's still struggling to understand human nature.
A character study (from the same fan site)